Process of treating molten metals and alloys with compositions containing lithium and products resulting from such treatment



Patented Aug. 2, 1932 UNITED STATES PATENT OFFICE HANS OSBORG, OF FRANKFORT-ON-THE-MAIN, GERMANY PROCESS OF TREATING MOLTEN METALS AND ALLOYS WITH COMPOSITIONS CONTAIN- ING LITHIUM AND PRODUCTS RESULTING FROM: SUCH TREATMENT No Drawing. Application filed December 21, 1931,

The present invention relates to a process of treating'metals and alloys in theirmolten state with a lithium-silicon composition or with a silicided alloy of lithium and a metal of the alkali group, including alkali and/or alkaline earth groups and/ or rare earth group and to the improved products resulting from such a process.

Heretofore, a great variety of scavengers and improvers of metals and alloys have been proposed. Of these scavengers and improvers, the more important were manganese, silicon, zinc, magnesium, phosphor and phosphides, metallic lithium metallic calcium,

calcium silicide and magnesium silicide, etc. From an industrial point of view manganese, silicon, zinc, magnesium, phosphor compounds and phosphides have been the most important, but the art was attempting to obtain better and more satisfactory resultsthan those obtained by the use of these substances. lVith this object in view, those skilled in the art were attempting to find improved scavengers. Metallic lithium'and metallic calcium were proposed, but it was found that these metals had shortcomings and disadvantages when used on an industrial scale. The more serious disadvantages were that the molten metal and alloy undergoing treatment was not cleaned completely, did notpossess the desired improved properties and usually was contaminated with impurities or contained blow holes. From a practical point of view, it was found that the use of these metals was not wholly economical and satisfactory on an industrial scale. Various suggestions have been made for remedying the short-comings and disadvantages noted hereinabove with respect toprior scavengers including metallic lithium and metallic calcium, calcium silicide and magnesium silicide, and/or processes of using the same, but, as far as is known, no scavenger and/or improver and/or process of using the same has been proposed which is wholly satisfactory and practical when used on an industrial scale.

It is an object of the present invention to provide a process of treating metals and alloys in their molten state so as to obtain the benefits resulting from lithium treat- Serial No. 582,494, and in Canada June 26, 1931.

ments without the disadvantage noted hereinabove.

It is a further object of the invention to provide a simple, economical and tho-roughly satisfactory process of treating metals and alloys in their molten state with active lithium-bearing substances so as to improve the characteristics thereof.

It is another object of my invention to provide a process of treating molten metals and molten alloys with a lithium-silicon com position or with a silicided lithium alloy of a metal of the alkali group or alkaline earth group or rare earth group which is capable of being carried into commercial practice on an industrial scale in the ferrous and the non-ferrous industries, which is also capable of producing greater effects than provided by the same amount of lithium and the like.

Other objects and advantages of the invention will become apparent from the following description.

Broadly stated, my invention contemplates the treatment of molten metals and alloys with a lithium-silicon composition or with a silicided lithium alloy of a metal of the alkali group or alkaline earth group or rare earth group in which the lithium is sobonded that the loss thereof through volatilization and the like is materially reduced. At the same time, the lithium-silicon composition or silicided lithium alloy can function actively to eli'ect improvements in the properties and qualities of the metallic substance under treatment. I have found that in carrying my invention into practice, that silicided lithium alloys containing members of the alkali or alkaline earth families such, for

example, as calcium, barium, strontium,

magnesium, sodium or potassium or relatively stable compositions of lithium and silicon or of mixtures of the foregoing substances can be utilized in the treatment of metals and alloys in their molten state so as to effect improvements in the properties and qualities in the metals or alloys treated.

The following examples are given for illustrative purposes and for a better understanding of carrying my invention into practice.

Example .N 0. I

In the treatment of iron or steel, for instance the molten metal is contained in a suitable crucible such as a graphite crucible bull ladle,ingot mold, etc. To the molten mass I add in any appropriate manner, an active lithium-silicon substance, for example, a silicided alloy of lithium and calcium in an amount sufficient to effect improvements in the properties of the iron or steel. In practice, I have found that up to about 2 parts of a silicided alloy of lithium and calcium having about a 50% lithium-calcium content are capable of effectively treating about 100 parts of molten steel or steel alloys.

The addition of the active lithium-silicon substance to the molten metal is preferably effected by plunging the selected amount of active lithium-silicon substance into the molten material in a crucible by any appropriate means such as an inverted cup with side openings or ports or the like. By adding the active silicon composition to the molten metal in the aforesaid manner, I am able to efi'ect a thorough distribution of the lithium-silicon composition throughout the molten mass and to effect the proper treatment of said metal to improve the properties and qualities thereof.

lVhen iron or steel or copper or nickel or alloys thereof are treated with one of my active lithium-silicon compositions or silicided alloys, the molten mass has a better fluidity and consequently, can be cast very much better than heretofore and gives better and denser casting. In addition, the physical properties of the iron or steel or metal or alloy treated are improved. For instance, there is an increased hardness and corrosive resistance of the metal thus treated and the finished product is relatively free from blow holes, oxygen sulphur and the like. W'henv nichrome is treated in this manner, it has a; better resistance than when untreated and can be worked and drawn to wire without any heat treatment.

Example N0. 2

When steel or a steel alloy is used for the production of castings, I add to about 100 parts of molten iron prior to casting enough of an active lithium bearing substance such as a composition of lithium and silicon or a. mixture of this composition with a lithium alloy, such as lithium-cerium to give a lithium content up to about 1%. The lithiumsilicon composition is preferably added in the form of a solid briquette or the like which is introduced into the molten mass of iron by means of an inverted cup or other appropriate instrumentality. The lithium thus added, improves the crystal structure of the steel combines with gases. such as oxygen and nitrogen, and also with such detrimental substances as sulphur and phosphorus; in-

creases the fluidity of the molten steel and produces denser and sounder casting than produced heretofore. In practice, I prefer to add the composition of lithium-silicon.

in amass wherein the composition of lithium and silicon is surrounded or coated with iron silicide. By adding the lithiunusilicon composition in this manner, the procedure is facilitated. If it is desired, other silicides such as calcium-silicidc or the like may also be added to the briquette containing the lithium-silicon composition. In place of a mixture of silicides, a lithium-calcium alloy can be silicided and then the silicided lithium al- 10y used for the treatment of the molten metal or alloy.

E wample N 0. 3

An improved cast iron was produced by treating 1500 parts of molten cast iron in a bull ladle with about 0.45 parts of a silicided lithium-calcium alloy. This alloy was introduced into the molten iron by the use of an inverted bell-shaped stirring utensil. By stirring the molten iron with the utensil,

a practically complete distribution of the silicided lithium-calcium alloy throughout the molten mass of cast iron was effected.

It was found that the cast iron so treated was of a much better grade than ordinary cast iron and possessed better and improved properties. The graphite present in the cast iron was broken up in very fine particles which were distributed practically evenly throughout the iron. The gases and oxygen were found to be practically completely removed. The mechanical properties including tensile strength and Brinell hardness were increased a substantial amount. The machinability was greatly improved in spite of the higher hardness of the improved cast iron. Moreover, the crystals in the cast iron were relatively small in contrast to the large crystals in ordinary cast iron. Furthermore,

'the improved cast iron had a uniform hardness in contrast to many of the old cast irons which contained hard spots. Moreover, the improved cast iron had a better fluidity in a molten condition and poured better than ordinary molten cast iron.

Example No. 4

inch, a Brinell hardness number of 119 and elongation of about and a reduction of area of about The corresponding ordinary carbon steel had a tensile strength of 50,000 lbs. per square inch and a Brinell hardness number of 98.5.

Ezvample N0. 5

An improved alloy steel such as a nickelchromium steel with 28% chromium and 10% nickel was produced by treating 700 parts of such steel with about 0.15 parts of silicided lithium-calcium alloy. 11 general, the present treatment produced an increase in temperature of the molten metal, a better fluidity of the molten bath, better castings, improved crystal structure, cleaner metal and superior metal with respect to physical and mechanical properties and an improved corrosion resistance.

An improved copper was produced by treating 1,200 parts of copper with 0.48 part of silicided lithiun'i-calcium alloy or lithiumstrontium alloy in a crucible. By properly agitating the silicided lithium-calcium alloy throughout the molten bath of copper, a uniform treatment was eflected. It was found that the conductivity of the copper increased materially and that electrical conductivities ranging from about 99% to 102% were obtained. In addition, unusually high densities were obtained in the improved copper and ranged from about 8.90 to about 8.94. The fractures showed excellent crystal structures, usually of the so-called sun-burst type (which is desirable for making seamless pipes) or a silky fine grained structure (which gives the copper excellent Working qualities). The foregoing improved copper showed in comparative tests that it had a specific gravity of about 8.92, a fracture rating of 100% and an electrical conductivity of 101.3% as against a phosphor treated copper which had a specific gravity of 8.83 and fracture rating of 93% and an electrical conductivity of 88% and as against a zinc treated copper with a specific gravity of 8.05, a fracture rating of 90% and an electrical conductivity of 97.6%. Photomicrographs showed I that improved copper when treated with the Example N0. 7

An improved nickel was produced by treating 700 parts of fairly good grade of scrap nickel with about 0.2 part of silicided lithiun'rcalcium alloy. The nickel resulting from this treatment was far superior to ordinary nickel. For comparative purposes, nickel was treated with 0.1% magnesium and it was found that nickel thus treated had many seams and large spots of nickel oxide on the grain boundaries of the crystals and did not possess the mechanical and physical properties of the present improved nickel. Tests show that the improved nickel when treated with silicided lithium-calcium alloy had higher strengths and possessed a better and cleaner crystal structure.

Example N0. 8

An improved Monel metal was obtained by treating 800 parts of molten Monel scrap with about 0.24 parts of the silicided lithium-calcium alloy. The cast monel showed higher tensile strengths and higher elongations than ordinary monel. For comparative purposes, a portion of molten Monel scrap metal was treated with magnesium in the customary manner and a second portion of Monel metal from the same heat was treated h the-present lithium-calcium alloy. Tests sh wed that the monel treated with magnesium p ssessed a tensile strength of about 37,000 to about 39,000 lbs. per square inch and an elongation of 6 to 11%, whereas the monel treated with the present silicided lithium-calcium alloy possessed a tensile strength of 58,000 to about 65,000 lbs. per square inch and an elongation of 18 to 25%. In addition, the photomicrographs showed that the improved Monel metal treated with the present silicided lithium-calcium alloy was clean, free from segregations and possessed a better crystal structure.

It is to be observed that the foregoing examples are illustrations of the present invention when carried into use on an industrial scale. The results, therefore, represent practical, commercial and industrial values and not merely results obtained from laboratory experiments. Although certain specific figures and examples have beeiu given those skilled in the art will appreciate that these are merely illustrati e and are not to be taken as the limitations of the inventon. For instance, instead of a silicided lithium-calcium alloy other alloys of lithium and a metal of the alkali or alkaline earth groups including hydrogen may be used. These alloys are, for instance, lithium-strontium, lithium-barium, lithium-sodium, lithium-potassium, lithiumhydrogen, hydrides of lithium alloys or o f metals of alkali, alkaline earth and rare earth groups. The practical, useful, economical and commercial range within which these silicided alloys may be used is from about 0.001% to about 0.50%. Of course, the amount of silicided lithium alloy added to the molten metallic mass depends upon a number of variables as one skilled in the art will readily understand. For example, the percentage of lithium in the silicided lithium alloy will determine in part how much of the alloy is to be used. Then again, the amount of impurities and gases in the molten metal or alloy and the improvement to be given to such metal or alloy will also have to be taken into account in determining the amount or percentage of silicided lithium alloy to be employed.

In instances where silicided alloys are used, it is preferred to silicide the lithium alloy in whole or in part in the following manner. By siliciding briquettes, blocks or units of the lithium alloy or lithium, a stable nonhygroscopic, and handable unit is produced. I have found that the utilization of high temperatures, say above 500 0., produce a high temperature lithium-silicon composition which is stable and non-hygroscopic. This new composition is distinctly different from old lithium-silicon compositions which were hygroscopic and which were produced under low temperatures, say under 500 C. The old low temperature composition had a formula of Li Sig and had to be made with an excess of lithium which was subsequently distilled from the silicidecomposition. The new high temperature lithium-silicon compositions in contrast to the old low temperature silicide can be made of any composition without the necessity of using an excess of lithium and of distilling the same after the formation of the silicide. This new composition and the process of producing the same are described and claimed in my (to-pending application, Serial No. 466,584, filed July 8, 1930.

The following examples are illustrative of the present method of producing silieided lithium compositions.

Example No. .0

A mixture containing about 53 parts lithium alloy and about 47 parts of silicon are heated in an appropriate crucible to a temperature of about 600 C. The heating is carried on under a vacuum which is preferably practically complete. After the lithium alloy is fused and the reaction temperature is reached, the lithium alloy and silicon combine with each other and form a fused mass. Upon cooling, in the fused mass a solid body of substantially uniform dark silvery gray it was found that the cr stals were non-deliquescent and could be andled in dry air.

E mample N 0. 10

A mixture of about 20.8 parts of lithium alloy and about 28.3 parts of silicon is heated in a crucible to a temperature of about 600 C. under practically a complete vacuum. After thoroughly reacting and fusing, the entire mass is permitted to solidify. The solidified body thus produced is dark gray in color on the outside and silvery gray on the inside and is constituted of a mass of small crystals. An analysis of the mass of the crystals made according to the foregoing method, showed that silicon was present to the extent of about 58-00%.- and lithium alloy was present to the extent of about 40-42%. The crystals acted ghe same as the crystals produced in Example Example N 0. 11

A mixture of about 41.6 parts of lithium all loy and about 28.0 parts of silicon are heated in a crucible to a temperature of about 000 C. The heating is carried on under a practically complete vacuum. A product produced in accordance with the foregoing has a silvery gray color which becomes discolored upon exposure to the air. A mass made by the foregoing method was found to contain about 10% silicon and about 60% lithium alloy. The crystals in said mass acted the same as noted in connection with Example No. 9.

In the foregoing examples, it has been specitied that the heating is effected in a vacuum but the invention is not limited to this mode of procedure. Furthermore, lithium may be used in place of the lithium alloy. Other appropriate procedures can be employed. For instance, instead of employing a vacuum, one may heat the lithium alloy and silicon in an atmosphere of inert gas or gases such as rare gases like helium. Instead of rare gases, an

atmosphere of lithium or silicon or a mixture thereof may be employed. A lithium atmos phere, however, is rather costly and it is recommended preferably heating the mixture of lithium alloy and silicon under a practically complete vacuum. Then again, the material may be reacted in the vapor state if it is desired.

In some cases, it has been found desirable to hydride the lithium alloy and/or a metal of the alkali, alkaline earth or rare earth group in whole or in part. The hydriding of the lithium alloy or the like may be carried into practice in any appropriate or suitable manner. In the present instance, it is preferred to hydride lithium or the lithium alloy by passing hydrogen in contact with lithium or the lithium alloy under the influence of heat. For example, lithium or lithium alloy may be placed in a vessel which is evacuated and which is then filled with hydro en. Byheating to about 500 C. and 750 the lithium or lithium alloy or the like hydrogen will be taken up thereby to form the hydride. A stream of hydrogen may also be passed through or into the vessel after it has been filled with hydrogen and while the heating is in progress. By continuing this procedure, for a suitable length of time, the desired hydriding of lithium or.

lithium alloy may be effected. It is to be noted that in treating metals and alloys with hydrided lithium or hydrided lithium alloys or the like, the metals and alloys are divided into two groups, one group having an afiinity for hydrogen and a second group which has little or no afiinity for hydrogen. In the first group are metals such as copper, iron, nickel, platinum, etc., and their alloys. The second group includes such metals as cadmium, lead, bismuth, antimony, gold, silver, zinc, tin, thallium, rhodium and others and their alloys. lVhen metals or alloys of the second group are treated, practically any amount of hydride can be added because the molten metal will not combine with the hydrogen when hot. In the first group, however, the metal or alloy dissolves an excess of hydrogen which is freed or liberated during freezing and is likely to form blow holes, imperfections and the like in the cast metal or alloy. It is, therefore, advisable to avoid the use of an excess of hydride when treating such metals and/or alloys. Depending upon the metal or alloy to be treated, various percentages of hydrides may be used.

It will be observed that the foregoing treatments of metals or alloys in their molten state maybe used separately or in combination. For instance, the molten metal or alloy may be first treated with about 0.015% of the hydrided lithium-calcium alloy. After said treatment, the molten metal or alloy may be subsequently treated with about 0.03% of a 50/50 lithium-calcium alloy. In the same way, other combination treatments may be used as one skilled in the art will readily understand.

In some instances, I prefer to employ an alloy of lithium with the metal or alloy to be treated. For example, if steel is to be treated, I use an active lithium alloy containing iron. In the same way, if nickel is to be treated, I use a lithium alloy containing nickel. The lithium alloys should preferably have a lithium content of about 50% and should be silicated or reacted with silicon prior to use.

It will also be observed that the present improver and scavenger may be hydrided. first and then silicided or vice versa. Thus, lithium or a lithium alloy may be partly hydrided as described in my application Serial No. 480,- 179, filed September 6, 1930, and then silicided or vice versa. Of course, if the present improver and scavenger is to contain a metal or alloy to be treated such as iron, nickel, copper, etc., such metal can be incorporated initially in the improver and scavenger and then bydrided and/or silicided. For instance, lithium or a lithium alloy such as lithium calcium may be hydrided first to any desired extent and then silicided. As is well known, the lithium or lithium-calcium or the like may be pre-alloyed with the metal or alloy to be treated, such as iron, nickel, copper, etc. The pre-alloyed lithium or lithium-calcium can be hydrided and/or silicided as explained hereinabove. Of course, the block, lump, mass or the like can be embedded in or coated with another material such as a silicide of iron, nickel, copper, etc. as described in my applications U. S. Serial No. 467,625, filed on July 12, 1930, U. s. Serial Nos. 582,490; 582,491 and 582,492, filed on December 21, 1931.

It will be noted that rare earth metals are to be considered as equivalent to alkaline earth metals and that when the latter metals are referredto in the specification and claims, they include the metals of the rare earth.

It will be observed that the lithium alloys referred to herein may be made in any appropriate manner as one skilled in the art will understand but I prefer to use the electrolytic method described in my application, U. S. Serial No. 466,583, filed July 8, 1930.

The present application is a continuation in part of my application, Serial No. 467,625, filed July 12, 1930.

When in the specification and claims, I use the term alkali, it is to be understood to include metals of the alkali family, the alkaline earth family and the rare earth family and also to include hydrogen which forms hydrides with lithium etc.

Moreover, when in the specification and the claims I refer to a trace of residual lithium or a trace of residual lithium composition, etc., I mean a trace'of lithium which is less than about 0.03% lithium.

Having now particularly described and as-. certained the nature of my said invention, and

in what manner the same is to be performed,

I declare that what I claim is:

1. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises treating said metals and/or alloys thereof while in a molten state with a lithium-silicon composition.

2. The process of treating metals including copper, iron, and nickel, and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises treating said metals and/or alloys thereof While in a molten state with a lithium-silicon composition, and regulating the amount of said lithiumsilicon composition used in the aforesaid operation up to about 2 arts of the lithiumsilicon' composition to a out 100 parts of the molten metallic mass treated.

3. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises establishing a molten mass of said metals and/or alloys, treating said mass by dipping a solid body of a lithium-silicon composition into a molten mass to be treated and stirringthe thus-treated molten mass to effect a thorough distribution of said lithium-silicon composition.

4. The process of treating metals including copper, iron, nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises adding a briquette containing a lithium-silicon composition, to a molten mass of said metals and/or alloys thereof to be treated and causing a thorough mixing of said lithium-silicon composition in said molten mass.

5. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises treatingsaid metals and/or alloys thereof while in a molten state with a lithium-alkali-silicon composition.

6. The process of treating metals including copper, iron, nickel and /or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises adding a lithium-calcium-silicon composition to a molten mass of metals and/or alloys thereof to be treated and stirring said molten mass to ef feet a treatment of the various parts of said mass with said lithium-calcium-silicon composition.

7. The process of treating metals including copper, iron, nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises dipping a solid body of lithium-calcium-silicon composition into the lower portion of a molten mass of the metals and/or alloys thereof to be treated and effecting a distribution of said lithiumcalcium-silicon composition substantially throughout said mass.

8. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises treating said netals and/or alloys thereof While in a molten state with a lithium-alkali-silicon composition, and regulating the amount of said lithium-alkali-silicon composition used in the aforesaid operation up to about 2 parts of the lithium-alkali-silicon composltion to about 100 parts of the molten metallic mass treated.

9. The process of treatin metals includin copper, iron, and nickel an /or alloys of such metals in their molten state to purify and scavenge the same and to improve the pro erties thereof, which comprises treating said metals and/ or alloys thereof while in a molten state with a lithium-calcium-silicon composition, and regulating the amount of said lithium-calcium-silicon composition used in the aforesaid operation up to about 2 parts of the lithium-calcium-silicon to about 100 parts of the molten mass treated.

10. The process of treating metals including copper, iron, nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises establishing a molten mass of "said metals and/or alloys, treating said mass by dipping a solid body of a lithium-alkali-silicon composition into a molten mass to be treated and stirring the thus-treated molten mass to effect a thorough distribution of said lithium-alkali"-silicon composition.

11. The process of treating metals including copper, iron, nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof which comprises adding a briquette containing lithium-calcium-silicon composition, to a molten mass of said metals and/or alloys thereof to be treated and causing a thorough mixing of said lithium-calcium-silicon composition in said molten mass.

12. The process of treatingmetals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises trcating said metals and /or alloys thereof while in a molten state with a lithium-silicon composition containing a metal or alloy to be treated.

13. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which-comprises treating said metals and/or alloys thereof while in a molten state with a hydrided lithium-silicon composition.

14. The process of treating metals including copper, iron, and nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the properties thereof, which comprises treating said metals and/or alloys thereof while in a molten state with a hydrided lithium-alkali-silicon composition.

15. The process of treating metals including copper, iron, nickel and/or alloys of such metals in their molten state to purify and scavenge the same and to improve the prop erties thereof which comprises adding a hydrided lithium-calcium-silicon composition to a molten mass of metals and/or alloys thereof to be treated and stirring said molten mass to effect a treatment of the various parts of said mass with said hydrided lithium-calcium-silicon composition.

16. The improved metals including copper, iron, and nickel and/ or alloys of such metals which comprises a metal and/or alloy thereof resulting from the treatment with a lithiumsilicon composition and containing a trace of residual lithium.

17. The improved metals including copper,

iron, and nickel and/or alloys of such metals which comprises a metal and/or alloy thereof resulting from the treatment with a lithiumalkali-silicon composition and containing a trace of residual lithium.

18. The improved metals including copper, iron, and nickel and/ or alloys of such metals which comprises a metal and/or alloy thereof resulting from the treatment with a lithiumcalcium-silicon composition and containing a trace of residual lithium.

19. The improved metals including copper, iron, and nickel and/or alloys of such metals which comprises a metal and/or alloy thereof resulting from the treatment with a hydrided lithium-silicon composition and containing a trace of residual lithium.

20. An article of manufacture comprising an improved metal including copper, iron, and nickel and/or alloy of such metal resulting from the treatment with a lithium-silicon composition and containing a trace of residual lithium-silicon composltion.

21. An article of manufacture comprising improved metal including copper, iron, and nickel and/or alloy of such metal resulting from the treatment with a lithium-silicon composition and containing a trace of residual lithium-alkali"-silicon composition.

22. An article of manufacture comprising improved metal including copper, iron, and nickel and/or alloy of such metal resulting from the treatment with a lithium-silicon composition and containing a trace of residual lithium-calcium-silicon composition.

23. An improvin g, purifying and scavenging agent for mo ten metals and alloys which comprises a lit ium-alkali-silicon composition.

24. An improving, purifying and scavenging agent for molten metals and alloys which comprises a. lithium-calcium-silicon composition.

25. An improving, purifying and scavenging agent for molten metals and alloys which comprises a hydrided high temperature lith- .iu'm-silicon-composition.

In testimony whereof I have hereunto set my hand.

HANS OSBORG. 

